1. Field of Invention
This invention relates to systems and methods for generating summaries of media stream that are representative of the structural character of the entire steam.
2. Description of Related Art
Media summarization technologies have numerous applications in e-commerce and information retrieval. Many such applications use summaries and/or proxies of longer works, because of the large file sizes and high bandwidth requirements of multi media data. The summary of the media work is reduced in some manner, typically by excerpting a segment or segments that are a good representation of the longer work. To identify segments that are a good representation of the longer work, the structure of the media stream must be determined.
U.S. Published patent application 2003/0048946, which is incorporated herein by reference in its entirety, discloses a method for assessing structure in media streams that includes three steps. In a first step, each window, which is either a single frame, or a short time unit, of the media stream, is parameterized by calculating a feature vector for that window. In a second step, a similarity measure is determined for every pair of windows based on the windows feature vectors. The similarity measures are embedded in a similarity matrix for analysis. In a third step, the similarity matrix is factored using Singular Value Decomposition (SVD) to determine the major structural elements of the media stream. The major structural elements or basis vectors are processed to determine segment boundaries and clusters of similar segments.
Once the major structural segments and the clusters of structural segments are identified, a single excerpt can be identified to represent each structural segment cluster by maximizing, for each excerpt, that excerpt's similarity to other members of the corresponding segment cluster. An excerpt for each significantly different segment of the media is generated, while redundant excerpts for similar structural segments in the same cluster are eliminated.
U.S. Published Patent Application 2003/0161396, which is incorporated herein by reference in its entirety, discloses a method for selecting a summary excerpt of a longer media source using similarity analysis. In that method, the similarity matrix is generated as outlined above in the first two steps of the incorporated 946 published application. The similarity matrix is then processed to determine the excerpt with maximal similarity to the entire source stream.